Max parallel http connections in a browser?

Question

I am creating some suspended connections to an HTTP server (comet, reverse ajax, etc). It works ok, but I see the browser only allows two suspended connections to a given domain simultaneously. So if a user is looking at my website in Tab1 of their browser, then also tries loading it in Tab2, they've used up the two allowed connections to my site.

I think I can do some wildcard domain thing, where I have my HTTP server resolve any address to my site like:

*.example.com/webapp  -> 192.0.2.1 (the actual ip of my server)

so:

a.example.com/webapp

b.example.com/webapp

c.example.com/webapp

all still point to (www.example.com/webapp) but the browser considers them different domains, so I don't run into the 2 connection limit. Is this true?

Even if that is true - is there any limit to the number of active connections per browser, across all domains? Say I use the scheme above - does Firefox for example only allow 24 parallel connections at any given time? Something like:

1) a.example.com/webapp

2) www.download.example/hugefile.zip

3) b.example.com/webapp

4) c.example.com/webapp

...

24) x.example.com/webapp

25) // Error - all 24 possible connections currently in use!

I just picked 24 connections/Firefox as an example.

Answer 1

Max Number of default simultaneous persistent connections per server/proxy:

Firefox 2:  2

Firefox 3+: 6

Opera 9.26: 4

Opera 12:   6

Safari 3:   4

Safari 5:   6

IE 7:       2

IE 8:       6

IE 10:      8

Chrome:     6

The limit is per-server/proxy, so your wildcard scheme will work.